A combination of fibre-rich rye bread and yoghurt containing Lactobacillus GG improves bowel function in women with self-reported constipation

The aim of the study was to investigate the effects of fibre-rich rye bread and yoghurt containing Lactobacillus GG (LGG) on intestinal transit time and bowel function, and to test whether they have an interaction in cases of self-reported constipation. The study was carried out as a two-by-two factorial design. Free-living subjects. A total of 59 healthy women with self-reported constipation, recruited by advertisement. After a baseline period, the subjects were randomized into four diet groups: (1) rye bread+LGG yoghurt, (2) rye bread, (3) LGG yoghurt, and (4) control. The 3-week dietary intervention was followed by a 3-week follow-up period. During each period, total intestinal transit time was measured and the subjects recorded faecal frequency and consistency, difficulty in defecation and gastrointestinal symptoms. The rye bread shortened total intestinal transit time (mean difference, −0.7; CI95, −1.1 to −0.2; P=0.007), increased faecal frequency (0.3; CI95, 0.1 to 0.5; P=0.001), softened faeces (−0.3; CI95, −0.4 to −0.2; P<0.001) and made defecation easier (−0.4; CI95, −0.5 to −0.2; P<0.001), but also increased gastrointestinal symptoms (1.6; CI95, 0.7 to 2.4; P<0.001) compared to the low-fibre toast consumed in the LGG and control groups. There were fewer symptoms in the rye bread+LGG group compared to the rye bread group (−1.3; CI95, −2.4 to −0.2; P=0.027). Fibre-rich rye bread can be recommended in the treatment of constipation, and the simultaneous consumption of LGG yoghurt relieves the adverse gastrointestinal effects associated with increased intake of fibre. Valio Ltd, R&D, and Fazer Bakeries Ltd.